GENERAL DESCRIPTION

The 74HC/HCT583 are high-speed Si-gate CMOS devices and are pin compatible with low power Schottky TTL (LSTTL). They are specified in compliance with JECEC standard no. 7A.

The 74HC/HCT583 are high-speed 4-bit BCD full adders with internal carry look-ahead. They accept two 4-bit decimal numbers (A0 to A3 and B0 to B3) and a carry input (CIN).

The “583” generates the decimal sum outputs (∑0 to ∑3) and a carry output (Cn+4) if the sum is greater than 9.

If an addition of two BCD numbers produce a number greater than 9, a valid BCD number and a carry will result. For input values larger than 9, the number is converted from binary to BCD. Binary to BCD conversion occurs by grounding one set of inputs, An or Bn and applying a 4-bit binary number to the other set of inputs. If the input is between 0 and 9, a BCD number occurs at the output. If the binary input falls between 10 and 15, a carry term is generated. Both the carry term and the sum are the BCD equivalent of the binary input. Converting binary numbers greater than 16 may be achieved by cascading “583s”.

See the “283” for the binary version.

FEATURES

• Adds two decimal numbers

• Full internal look-ahead

• Fast ripple carry for economical expansion

• Output capability: standard driver

• ICC category: MSI